Introduction: In 2020, 16% of deaths among kidney transplant (KT) recipients in the United States were due to COVID-19, and KT recipients remain at high risk for severe complications. The impact of vaccination on COVID-19 outcomes in KT recipients remains incompletely described.  Our aim was to review the outcomes of our center’s KT recipients who contracted COVID-19 after the availability of vaccines.

Methods: We retrospectively reviewed all KT recipients at Wake Forest Baptist Medical Center (Winston-Salem, North Carolina, USA) performed between 2016 and 2020 with a known laboratory-proven diagnosis of COVID-19 from 03/2021 through 02/2022. Demographic, vaccination, hospitalization and outcome information were reviewed for these patients.

Results: 1017 patients underwent kidney transplantation at our center between 2016-2020, including 11 patients who died of COVID-19 complications prior to March 2021. We identified 58 patients (5.7%) with laboratory-proven COVID-19 between March 2021 and February 2022. Of these patients, 33 (56.9%) were men and 25 (43.1%) were women. The average age at COVID-19 diagnosis was 53 years (+/- 16.8). 27 patients (46.4%) were Black, 24 (41.4%) were White, 1 (1.7%) was Native American, and the remaining 7 (10.3%) were Asian, Native American, or other groups. 5 (8.6%) identified as Hispanic/Latino. Compared with the total KT population for the study period, COVID-19 was diagnosed in 33/539 (6.1%) of men, 25/478 (5.2%) of women, 24/518 (4.6%) of White patients, 27/414 (6.5%) of Black patients, 5/50 (10%) of Hispanic/Latino patients, and 7/85 (8.2%) of other groups. Of the patients with COVID-19, 42/58 (72.4%) had received at least one vaccine dose. 8 patients were infected with COVID-19 between 3/1/21 and 6/30/21, 16 during the Delta variant from 7/1/21 to 11/15/21, and 34 during the Omicron variant from 11/16/21 and 3/1/2022. Venous thromboembolism occurred in 7/58 patients (12.1%), acute kidney injury in 26/58 (44.8%), and transplant rejection in 1/58 (1.7%). Overall, 31/58 patients required hospitalization (53.4%), 10/58 required ICU admission (17.2%), and 6/58 died (10.3%). Of these deaths, 5 occurred in the hospital, while 1 occurred at home shortly after hospital discharge.

Conclusion: In this single-center analysis, we identified a high risk for severe complications of COVID-19 in KT recipients, even with vaccination. Overall, COVID-19 mortality was lower following vaccine availability in our center compared with the pre-vaccine period. Our present cohort size is almost certainly an underestimate, but there was a marked increase in diagnosed cases during the Omicron wave compared with earlier variants. A majority of identified patients required hospitalization, with a high risk for death. Infection appeared more common in minority groups and in men. Continued precautions will be necessary to protect KT recipients during the ongoing pandemic.